James Parker of England was born gay. He realized he was attracted to other boys at the young age of 10, he was accepted by his family when he came out in his teens, and as an adult he had boyfriends and slept with, by his own estimate, over 200 men. Then he found a new relationship with Jesus Christ and converted to heterosexuality, complete with a wife and child. It turns out that Parker wasn't born that way, he just had a commitment problem that centered from his fear of heterosexual men.
I realised I had some issues, centring on commitment. I discovered I had a deep-rooted fear of rejection, I was too anxious, and I used people. I had an innate fear of men – not of their homophobia, but the real thing: a chasm between me and the normal heterosexual male (Kinsey's so-called number ones). [The Kinsey Scale goes from 0-6]
[…]
I eventually came to realise that as a boy I had failed to interact with other men on any significant level. I had perceived myself to be rejected by men even as a small boy and had made an inner vow never to deeply trust them. People had reached out to me and I had spurned them, including my father and two older brothers. No wonder men had become a mystery to me and even an obsession by my teens, when I began erotically craving men and feeding this through porn.
So because he was scared of straight men, he became attracted to gay men. Makes sense. Because of his experiences and because he was able to be attracted to and sexually satisfied by a woman, Parker now firmly believes that people aren't born gay, that they just create "hidden identities." However, it's not an uncommon thing for someone to not be gay and yet be attracted to the same sex while still being attracted to the opposite sex. These people are called "bisexuals."